In the client-server network architecture of the Internet and/or the Web, electronic documents are stored in computer systems running server programs and are accessed by computer systems running client programs. For example, information on the Web is provided by Web servers and is accessible by a client program such as a Web browser (e.g., Netscape's Navigator, Microsoft's Internet Explorer, or Java's micro-browser).
Information on the Internet and/or Web may be represented by specially formatted text files (e.g., Web pages) written in Hypertext Markup Language (“HTML”) or some other markup language, such as XML, HDML, and/or VRML. Each text file may be identified by a network address such as a Universal Resource Locator (“URL”). A typical Web page may include one or more hyperlinks referring to the network addresses of other Web pages. Hyperlinks may be displayed as underlined text or graphical images that, when clicked, send a request for the associated page. For example, when a hyperlink in a home page is selected, a request is sent out by the client to the address specified in the hyperlink, and the associated Web page is downloaded and displayed, by replacing the home page on the user's screen with the associated Web page.
Browsers and other client programs typically use a communications protocol such as Hypertext Transfer Protocol (“HTTP”) to request pages from Web servers. HTTP is a request/response protocol. Through a connection established between a client and a server, the client sends a request to the server, and the server provides a response to the client.
An Internet service provider (“ISP”) may be used to provide subscribers with access to the Internet and/or the World Wide Web (“Web”). In general, a subscriber relies on an ISP to provide computers that are connected to and therefore enable communication over the Internet and/or the Web. An ISP may offer services in addition to basic Internet access such as, for example, providing e-mail and instant messaging services that enable electronic communication, Web-hosting services that allow subscribers to publish homepages, newsgroup services that allow subscribers to read and post to newsgroups, and image services that allow subscribers to view and order digital images of pictures from a developed film roll.